KR101892856B1 - Polarizing plate and liquid crystal display comprising the same - Google Patents

Abstract

The present invention relates to a polarizing plate and a liquid crystal display device including the same.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polarizing plate and a liquid crystal display device including the polarizing plate.

The present application is based on Korean Patent Application No. 10-2016-0054218 filed on May 2, 2016, and Korean Patent Application No. 10-2016-0054216 filed on May 2, 2016 with the Korean Intellectual Property Office The contents of which are incorporated herein by reference in their entirety.

The present invention relates to a polarizing plate and a liquid crystal display device including the same.

The polarizing plate is useful as an optical component constituting a liquid crystal display device. Conventionally, as a polarizing plate, those having a structure in which a protective layer containing a transparent resin film is laminated on one side or both sides of a polarizing film by using an aqueous adhesive or the like is used.

A triacetyl cellulose film (TAC film) is widely used as such a transparent resin film because of its excellent optical transparency and moisture permeability. The polarizing plate is bonded to the liquid crystal cell with a pressure-sensitive adhesive through another optically functional layer as required, and inserted into the liquid crystal display device.

Polarizers used in the polarizer are iodine-dyed uniaxially stretched PVA-based films. Thin films and weak strength are required, so a protective film is required. However, TAC film, which is a polarizer protective film which is mainly used in the prior art, is poor in wet heat resistance and poor in pencil hardness and scratch resistance, so a separate hard coating is required.

The TAC or acrylic film of the lower polarizer of the display faces diffuser or prism film or DBEF film among the backlight unit. Today, the display is becoming thinner and larger, but the gap between the lower pol and the BLU is reduced and the lower polarizer is stuck, resulting in a shattering of the protective film (TAC, acrylic film) of the lower polarizer, There is a problem in that it is lowered.

In addition, a protective film for protection of a base film such as TAC / acrylic is required during the operation of the polarizing plate. When the protective film of the lower polarizer is removed at the assembly stage of the final product, static electricity may be generated, have. Therefore, there is a problem that the process cost is increased because an antistatic function protective film must be used to provide an electrostatic discharge (ESD) prevention function.

Therefore, it is urgent to develop a polarizing plate capable of improving the quality of products by minimizing the generation of static electricity while reducing the process cost.

Korean Patent Publication No. 10-2010-003717

A polarizing plate according to the present invention and a liquid crystal display device including the same.

The present application relates to a substrate film; An adhesive layer provided on one surface of the base film; A photocurable resin layer provided on one surface of the adhesive layer; And a protective film provided on one surface of the photocurable resin layer, wherein the photocurable resin layer comprises a polyfunctional acrylate-based monomer and an acrylate-based oligomer or acrylic-based elastic polymer having an elongation of 5 to 200% A curing resin, a photopolymerization initiator, and an antistatic agent, wherein the protective film has an antistatic surface on the other surface opposite to the surface facing the photocurable resin layer.

The present application also relates to a backlight unit; A liquid crystal panel provided on one surface of the backlight unit; And a polarizing plate provided between the backlight unit and the liquid crystal panel according to the present application.

The polarizing plate according to one embodiment of the present application can prevent circuit damage due to the generation of static electricity when the protective film is peeled because the photo-curable resin layer has a low sheet resistance and an antistatic function for the protective film.

In addition, the polarizing plate according to one embodiment of the present application can easily peel off the protective film, and at the same time, has a peeling force with which the interface adhesion with the protective film is effective, thereby securing excellent fairness.

In addition, the polarizing plate according to one embodiment of the present application exhibits high hardness, scratch resistance, and high transparency and does not generate curls or cracks due to excellent processability, and thus can be applied to various display devices. It can be thinned by applying without any coating. In addition, it exhibits excellent workability and flexibility, and is applicable to a large area or curved surface display.

1 is a view showing a polarizing plate according to an embodiment of the present application.
2 is a view showing a liquid crystal display device according to an embodiment of the present application.

Hereinafter, the present invention will be described in more detail.

Referring to FIG. 1, one embodiment of the present application includes a substrate film 110; An adhesive layer 120 provided on one surface of the base film; A photocurable resin layer 130 provided on one side of the adhesive layer; And a protective film (140) provided on one surface of the photocurable resin layer, wherein the photocurable resin layer comprises a polyfunctional acrylate-based monomer and an acrylate-based oligomer having a elongation of 5 to 200% , A photopolymerization initiator, and an antistatic agent. The base film, the adhesive layer, the photocurable resin layer, and the protective film may be sequentially provided as shown in FIG.

The base film used in one embodiment of the present application may be made of a polyvinyl alcohol-based resin, and specifically, a dichromatic dye is adsorbed and oriented on a uniaxially stretched polyvinyl alcohol-based resin film.

The polyvinyl alcohol-based resin constituting the base film is obtained by saponifying a polyvinyl acetate-based resin. Examples of the polyvinyl acetate resin include polyvinyl acetate, which is a homopolymer of vinyl acetate, and copolymers of vinyl acetate and other monomers copolymerizable therewith. Examples of other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, unsaturated sulfonic acids, olefins, vinyl ethers and the like. The saponification degree of the polyvinyl alcohol-based resin is usually about 85 to 100 mol%, specifically 98 to 100 mol%. The polyvinyl alcohol resin may be further modified. For example, polyvinyl formal or polyvinyl acetal modified with aldehydes may be used. The degree of polymerization of the polyvinyl alcohol-based resin is usually about 1,000 to 10,000, specifically about 1,500 to 10,000.

Such a polyvinyl alcohol-based resin film is used as the original film of the polarizing film. The method of forming the polyvinyl alcohol-based resin is not particularly limited, and a film can be formed by a known method. The thickness of the original film containing the polyvinyl alcohol-based resin is not particularly limited, but is, for example, about 10 μm to 150 μm.

The base film can be produced by a process comprising uniaxially stretching a disc film made of a polyvinyl alcohol-based resin as described above, a process of dyeing the polyvinyl alcohol-based resin film with a dichroic dye to adsorb the dichroic dye, A step of treating the adsorbed polyvinyl alcohol based resin film with an aqueous solution of boric acid, and a step of washing with water after treatment with an aqueous solution of boric acid.

Uniaxial stretching may be performed before or after dyeing with the dichroic dye, or may be performed after dyeing. When uniaxial stretching is performed after dyeing with a dichroic dye, the uniaxial stretching may be performed before the boric acid treatment or during the boric acid treatment. It is also possible to perform uniaxial stretching in these plural steps. In the uniaxial stretching, the uniaxial stretching may be performed between the different rolls of the main yarn, or may be elongated uniaxially using the heating roll. Further, it may be dry stretching such as stretching in the atmosphere, or wet stretching in which stretching is performed in a state of being swollen with a solvent. The stretching magnification is usually about 4 to 8 times.

In order to dye a polyvinyl alcohol-based resin film with a dichroic dye, for example, a polyvinyl alcohol-based resin film can be dipped in an aqueous solution containing a dichroic dye. As the dichroic dye, iodine, a dichroic dye and the like are used. It is preferable that the polyvinyl alcohol-based resin film is subjected to immersion treatment in water before the dyeing treatment.

When iodine is used as the dichroism dye, a dyeing method is usually employed in which a polyvinyl alcohol resin film is immersed in an aqueous solution containing iodine and potassium iodide. The content of iodine in this aqueous solution is usually about 0.01 to 0.5 parts by weight based on 100 parts by weight of water, and the content of potassium iodide is usually about 0.5 to 10 parts by weight based on 100 parts by weight of water. The temperature of the aqueous solution used for dyeing is usually about 20 to 40 占 폚, and the immersion time (dyeing time) in this aqueous solution is usually about 30 to 300 seconds.

On the other hand, when a dichroic dye is used as the dichroic dye, a dyeing method is usually employed in which a polyvinyl alcohol resin film is immersed in an aqueous dye solution containing a water-soluble dichroic dye. The content of the dichroic dye in the dye aqueous solution is usually about 1 × 10 ^-3 to 1 × 10 ^-2 parts by weight based on 100 parts by weight of water. The dye aqueous solution may contain an inorganic salt such as sodium sulfate as a dyeing aid. The temperature of the dye aqueous solution is usually about 20 to 80 DEG C, and the immersion time (dyeing time) in the dye aqueous solution is usually about 30 to 300 seconds.

The boric acid treatment after dyeing with the dichroic dye is carried out by immersing the dyed polyvinyl alcohol resin film in an aqueous solution containing boric acid. The content of boric acid in the aqueous solution containing boric acid is usually about 2 to 15 parts by weight, specifically about 5 to 12 parts by weight, based on 100 parts by weight of water. When iodine is used as the dichroic dye, it is preferable that the aqueous solution containing boric acid contains potassium iodide. The content of potassium iodide in the boric acid-containing aqueous solution is usually about 2 to 20 parts by weight, preferably about 5 to 15 parts by weight based on 100 parts by weight of water. The immersing time in the boric acid-containing aqueous solution is usually about 100 to 1,200 seconds, specifically about 150 to 600 seconds, more specifically about 200 to 400 seconds. The temperature of the boric acid-containing aqueous solution is usually 50 ° C or higher, specifically 50 to 85 ° C.

The polyvinyl alcohol resin film after boric acid treatment is usually subjected to water washing treatment. The water washing treatment is carried out, for example, by immersing a boric acid-treated polyvinyl alcohol resin film in water. The temperature of water in the water washing treatment is usually about 5 to 40 占 폚, and the immersion time is about 2 to 120 seconds. After washing with water, drying treatment is carried out to obtain a base film. The drying treatment can be performed using a hot-air dryer or a far-infrared heater. The drying temperature is usually about 40 to 100 占 폚. The time for the drying treatment is usually about 120 to 600 seconds.

The polarizing film in which the dichromatic dye is adsorbed and oriented on the uniaxially stretched polyvinyl alcohol-based resin film can be produced as described above. The thickness of the base film may be 20 to 80 占 퐉, specifically 20 to 50 占 퐉.

In addition, the photocurable resin layer according to one embodiment of the present application may be provided on one side of the adhesive layer, and a functional element including an antistatic function may be applied to the polarizing plate. In order to impose the functional element, the photocurable resin layer may include a cured resin of a polyfunctional acrylate-based monomer and an acrylate-based oligomer having a elongation of 5 to 200%, a photopolymerization initiator, and an antistatic agent.

The polyfunctional acrylate-based monomer includes two or more acrylate-based functional groups and has a molecular weight of less than 1,000 g / mol. More specifically, there can be mentioned, for example, hexanediol diacrylate (HDDA), tripropylene glycol diacrylate (TPGDA), ethylene glycol diacrylate (EGDA), trimethylolpropane triacrylate (TMPTA), trimethylolpropane ethoxy tri Acrylate (TMPEOTA), glycerin propoxylated triacrylate (GPTA), pentaerythritol tetraacrylate (PETA), or dipentaerythritol hexaacrylate (DPHA). However, the polyfunctional acrylate But the rate-based monomers are not limited thereto. The polyfunctional acrylate-based monomer is crosslinked with each other or cross-linked with an acrylate-based oligomer to be described later to give a certain strength and abrasion resistance to the photocurable resin layer.

The polyfunctional acrylate monomers may be used alone or in combination of two or more.

The acrylate oligomer is an acrylate having an elongation of from about 5 to about 200%, or from about 5 to about 100%, or from about 10 to about 50%, as measured by ASTM D638, Or more oligomers. When the elongation of the acrylate oligomer is in the above range, excellent flexibility and elasticity can be exhibited without deteriorating the mechanical properties. The acrylate oligomer satisfying the above elongation ranges is excellent in flexibility and elasticity to form the acrylate-based monomer and the cured resin, and can impart sufficient flexibility and curl characteristics to the photocurable resin layer containing the acrylate-based monomer have.

According to one embodiment of the present application, the weight average molecular weight of the acrylate oligomer ranges from about 1,000 to about 10,000 g / mol, or from about 1,000 to about 5,000 g / mol, or from about 1,000 to about 3,000 g / mol Lt; / RTI >

According to one embodiment of the present application, the acrylate oligomer is an acrylate-based oligomer modified with at least one of urethane, ethylene oxide, propylene oxide, and caprolactone Oligomers. When the modified acrylate oligomer is used, flexibility is further imparted to the acrylate oligomer due to modification, so that the curling property and flexibility of the photocurable resin layer can be increased.

The acrylate-based oligomer may be used alone or in combination with other types, for example, the acrylate-based elastic polymer.

The acrylate-based elastic polymer is excellent in flexibility and elasticity and has a weight average molecular weight of about 100,000 to about 800,000 g / mol, or about 150,000 to about 700,000 g / mol, Can range from about 180,000 to about 650,000 g / mol.

The protective film formed using the coating composition comprising the acrylate-based elastic polymer can ensure high elasticity or flexibility while securing mechanical properties, and can minimize curl or cracking .

According to one embodiment of the present application, the acrylate-based elastic polymer has an elongation of from about 5 to about 200%, or from about 5 to about 100%, or from about 10 to about 50%, as measured by ASTM D638 . When the elongation of the polyfunctional acrylate-based elastic polymer is in the above range, excellent flexibility and elasticity can be exhibited without deteriorating the mechanical properties.

An example of the acrylate-based elastic polymer is polyrotaxane.

Generally, polyrotaxane refers to a compound in which a dumbbell shaped molecule and a macrocycle are structurally intercalated. The dumbbell-shaped molecule is a linear molecule and a linear molecule of such a linear molecule. Wherein the linear molecule penetrates the interior of the cyclic compound and the cyclic compound can migrate along the linear molecule and is prevented from being released by the sequestering agent.

According to one embodiment of the present application, the polyrotaxane is a cyclic compound having a lactone compound to which an acrylate compound is introduced at the terminal thereof; Linear molecules passing through the cyclic compound; And a blocking group disposed at both ends of the linear molecule to prevent the elimination of the cyclic compound.

The cyclic compound can be used without any limitations as far as it has a size enough to penetrate or surround the linear molecule. The cyclic compound may be a compound having a hydroxyl group, an amino group, a carboxyl group, a thiol group or an aldehyde group Functional groups. Specific examples of such cyclic compounds include? -Cyclodextrin,? -Cyclodextrin,? -Cyclodextrin, and mixtures thereof.

In addition, as the linear molecule, a compound having a straight chain form can be used without any limitation if it has a molecular weight of a certain level or higher, but a polyalkylene compound or a polycaprolactone group can be used. Specifically, a polyoxyalkylene compound containing an oxyalkylene repeating unit having 1 to 8 carbon atoms or a polycaprolactone group having a lactone repeating unit having 3 to 10 carbon atoms can be used.

And, such linear molecules may have a weight average molecular weight of about 1,000 to about 50,000 g / mol. If the weight average molecular weight of the linear molecule is too small, the protective film produced using the linear molecule may have insufficient mechanical properties or self-healing ability. If the weight average molecular weight is too large, The uniformity of properties and materials may be greatly reduced.

On the other hand, the blocking group can be appropriately controlled in accordance with the properties of the polyrotaxane to be produced, and includes, for example, one kind selected from the group consisting of a dinitrophenyl group, a cyclodextrin group, an adamantane group, a trityl group, Two or more species can be used.

Another example of the acrylate-based elastic polymer is a urethane-based acrylate polymer. The urethane-based acrylate polymer has a form in which urethane-based acrylate oligomers are side-linked to the main chain of the acrylic polymer.

The photocurable resin layer of the present application includes the above-mentioned polyfunctional acrylate-based monomer and an acrylate-based oligomer having an elongation of 5 to 200%, which is cured by ultraviolet rays. In addition, the photocurable resin layer of the present application does not contain a triacetyl cellulose (TAC) component.

Examples of the photopolymerization initiator include 1-hydroxy-cyclohexyl-phenylketone, 2-hydroxy-2-methyl- 2-benzoyl-2- (dimethylamino) -1- [4- (4-methoxyphenyl) -2-methyl-1-propanone, methylbenzoylformate, -Morpholin yl) phenyl] -1-butanone, 2-methyl-1- [4- (methylcio) , 6-trimethylbenzoyl) -phosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, and the like. Products currently on the market include Irgacure 184, Irgacure 500, Irgacure 651, Irgacure 369, Irgacure 907, Darocur 1173, Darocur MBF, Irgacure 819, Darocur TPO, Irgacure 907 and Esacure KIP 100F. These photopolymerization initiators may be used alone or in combination of two or more.

In addition, the antistatic agent is dispersed in the photocurable resin layer, so that electrification of the photocured resin layer can be prevented. The polarizing plate is bonded to the photo-curable resin layer through a pressure-sensitive adhesive layer provided on the photo-cured resin layer, for example, when peeling off the release film adhered to the surface of the photo-curable resin layer, It is possible to prevent the static electricity from being charged when the polarizing plate is peeled off, and it is possible to effectively suppress destruction of the liquid crystal driver part of the liquid crystal display device due to static electricity.

The photocurable resin layer of the present application does not need to be provided with an antistatic layer separately because the antistatic agent is dispersed in the photocurable resin layer itself, which is a cured product of the curable composition, to give the antistatic function to the protective layer itself. Therefore, according to the present application, it is possible to further reduce the thickness and weight of the polarizing plate. Further, by employing a cured product of a curable composition containing an antistatic agent as a protective layer, the provision of the antistatic function to the protective layer and the thinning of the polarizing plate accompanying the elimination of the antistatic layer, It is possible to reduce the thickness of the polarizing film, improve the adhesion with the polarizing film, improve the hardness of the protective layer, and improve the shrinking suppressing ability of the polarizing film.

The antistatic agent is not particularly limited, and examples thereof include ionic compounds, conductive fine particles, and conductive polymers. Examples of the ionic compound include an ionic compound having an organic cation and an ionic compound having an inorganic cation.

The ionic compound having an organic cation is not particularly limited, but 1-butylpyridinium tetrafluoroborate, 1-butylpyridinium hexafluorophosphate, 1-butyl-3-methylpyridinium tetrafluoroborate, 1 Butyl-3-methylpyridinium bis (trifluoromethanesulfonyl) imide, 1-butyl-3-methylpyridinium bis (pentafluoro Ethanesulfonyl) imide, 1-butyl-4-methylpyridinium hexafluorophosphate, 1-hexylpyridinium tetrafluoroborate, 1-hexylpyridinium hexafluorophosphate, 1-octylpyridinium hexafluoro Ethyl indole tetrafluoroborate, 1-ethyl indole tetrafluoroborate, 1-ethyl indole tetrafluoroborate, 1-ethyl indole tetrafluoroborate, 1-ethyl indole tetrafluoroborate, Ethyl-3-methylimidazolium tetra Methylimidazolium trifluoroacetate, 1-ethyl-3-methylimidazolium heptafluorobutyrate, 1-ethyl-3-methylimidazolium acetate, 3-methylimidazolium trifluoromethanesulfonate, 1-ethyl-3-methylimidazolium perfluorobutanesulfonate, 1-ethyl-3-methylimidazolium dicyanamide, 1-ethyl- Methylimidazolium bis (trifluoromethanesulfonyl) imide, 1-ethyl-3-methylimidazolium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-3-methylimidazolium tris Butyl-3-methylimidazolium methanesulfonate, 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexa Butyl-3-methylimidazolium trifluoroacetate, 1-butyl-3-methylimidazolium heptafluorobutyrate, 1-butyl-3-methyl Butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide, 1-butyl-3-methylimidazolium perfluorobutanesulfonate, 1- Methylimidazolium bromide, 1-hexyl-3-methylimidazolium chloride, 1-hexyl-3-methylimidazolium tetrafluoroborate, 1-hexyl-3-methylimidazolium hexafluoro 1-hexyl-3-methylimidazolium trifluoromethanesulfonate, 1-octyl-3-methylimidazolium tetrafluoroborate, 1-octyl-3-methylimidazolium hexafluorophosphate, 1 -Hexyl-2,3-dimethylimidazolium tetrafluoroborate, 1,2-dimethyl-3-propylimidazolium bis (trifluoromethanesulfonyl) imide, 1-ethyl- Ethyl-3-methylimidazolium-p-toluenesulfonate, 1-methylpyrazolium tetrafluoroborate, 3-methylpyridinium tetrafluoroborate, Pyrazolium tetrafluoroborate, 1-butyl-1-methylpyrrolidinium hexafluorophosphate, tributylammonium hexafluorophosphate, tetrabutylammonium-p-toluenesulfonate, tetrahexylammonium bis (trifluoromethane sulphate N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium tetrafluoroborate, N, ) Ammonium bis (trifluoromethanesulfonyl) imide, diallyldimethylammonium tetrafluoroborate, diallyldimethylammonium trifluoromethanesulfonate, diallyldimethylammonium bis (trifluoromethanesulfonyl) imide, (Pentafluoroethanesulfonyl) imide, glycidyltrimethylammonium trifluoromethanesulfonate, glycidyltrimethylammonium bis (trifluoromethanesulfonyl) imide, glycidyltrimethylammonium Bis (pentafluoro Butylpyridinium (trifluoromethanesulfonyl) trifluoroacetamide, 1-butyl-3-methylpyridinium (trifluoromethanesulfonyl) trifluoroacetamide, 1- Ethyl (3-methylimidazolium) trifluoroacetamide, diallyldimethylammonium (trifluoromethanesulfonyl) trifluoroacetamide, glycidyltrimethylammonium (trifluoromethane Sulfonyl) trifluoroacetamide, N, N-dimethyl-N-ethyl-N-propylammonium bis (trifluoromethanesulfonyl) imide, N, (Trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl-N-pentylammonium bis (trifluoromethanesulfonyl) N, N-dimethyl-N-ethyl-N-heptylammonium bis (trifluoromethanesulfonyl) imide, N, N- (Trifluoromethanesulfonyl) imide, N, N-dimethyl-N, N-dipropylammonium bis (trifluoromethanesulfonyl) imide, N, N N-dimethyl-N-propyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl- , N, N-dimethyl-N-propyl-N-hexylammonium bis (trifluoromethanesulfonyl) imide, N, N, N-dimethyl-N-butyl-N-hexylammonium bis (trifluoromethanesulfonyl) imide, N, (Trifluoromethanesulfonyl) imide, N, N-dimethyl-N, N-dihexylammonium bis (trifluoromethanesulfonyl) imide, ) Imide, trimethylheptylammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-methyl-N-propylammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-methyl-N-pentylammonium bis (trifluoromethanesulfonyl N, N-diethyl-N-methyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, (Trifluoromethanesulfonyl) imide, triethylpentylammonium bis (trifluoromethanesulfonyl) imide, triethylpentylammonium bis (trifluoromethanesulfonyl) imide, triethylheptylammonium bis N, N-dipropyl-N-methyl-N-ethylammonium bis (trifluoromethanesulfonyl) imide, N, (Trifluoromethanesulfonyl) imide, N, N-dipropyl-N-butyl-N-hexylammonium bis (trifluoromethanesulfonyl) Ammonium bis (trifluoromethanesulfonyl) imide, N, N-di (Trifluoromethanesulfonyl) imide, N, N-dibutyl-N-methyl-N-hexylammonium bis (trifluoromethanesulfonyl) imide, tri Octylmethylammonium bis (trifluoromethanesulfonyl) imide, trioctylmethylammonium hexafluorophosphate, N-methyl-N-ethyl-N-propyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide (2-hydroxyethyl) trimethylammonium bis (trifluoromethanesulfonyl) imide, and (2-hydroxyethyl) trimethylammonium dimethylphosphinate.

Examples of the ionic compound having an inorganic cation include, but are not limited to, lithium bromide, lithium iodide, lithium tetrafluoroborate, lithium hexafluorophosphate, lithium thiocyanate, lithium perchlorate, lithium trifluoromethanesulfonate, Lithium bis (trifluoromethanesulfonyl) imide, lithium bis (pentafluoroethanesulfonyl) imide, lithium tris (trifluoromethanesulfonyl) imide and the like.

Examples of the conductive fine particles include, but not limited to, antimony-doped tin oxide, phosphorus-doped tin oxide, antimony oxide, zinc antimonate, titanium oxide, zinc oxide, indium tin oxide (ITO) ), And the like.

Examples of the conductive polymer include polyaniline, polypyrrole, polyacetylene, and polythiophene.

Of the above-mentioned antistatic agents, ionic compounds are preferably used because they are excellent in compatibility with active energy ray-curable compounds, more preferably ionic compounds having organic cations, and ionic compounds having organic cations It is more preferable to use an onium-based compound.

These antistatic agents may be used alone or in combination of two or more. Examples of the antistatic agent are not limited to those listed above.

According to one embodiment of the present application, the cured resin comprises a polyfunctional acrylate-based monomer and an acrylate-based oligomer having an elongation of 5 to 200% in the range of about 2: 8 to about 8: 2, or about 3: 7 to about 7: 3, or from about 4: 6 to about 6: 4. When the cured resin is cured to the above range, the photocurable resin layer of the present application can have sufficient flexibility without deteriorating the mechanical properties.

The photocurable resin layer of the present application includes a cured resin in which a polyfunctional acrylate-based monomer and an acrylate-based oligomer having an elongation of 5 to 200% are cured, so that high hardness and thinness can be achieved without lowering optical properties. It is also excellent in surface hardness and scratch resistance without a separate functional coating layer such as a hard coating. In addition, excellent flexibility, impact resistance, and flexibility can be secured, and the present invention can be applied to a large area or a curved surface display. Since it contains a cured resin layer that is not a stretched film, the retardation value is substantially as low as zero and can be used for various display devices requiring a low retardation value as well as a polarizer protective film without any limitations in its application.

The photocurable resin layer according to the present application contains a cured resin obtained by cross-linking an acrylate oligomer together with the above-mentioned polyfunctional acrylate monomer, so that it can exhibit high hardness and flexibility at the same time. Accordingly, the polarizer protective layer can function as a hard coating layer without a separate functional coating layer, and can be applied as a multifunctional polarizer photo-curable resin layer.

According to one embodiment of the present application, the photocurable resin layer of the present application may further include inorganic fine particles. The inorganic fine particles may be dispersed in the cured resin.

The inorganic microfine particle may be an inorganic microfine particle having a nanoscale particle size, for example, a particle size of about 100 nm or less, or about 10 to about 100 nm, or about 10 to about 50 nm. The inorganic fine particles may include, for example, silica fine particles, aluminum oxide particles, titanium oxide particles, or zinc oxide particles.

By including the inorganic fine particles, the hardness of the photo-curable resin layer can be further improved.

According to an embodiment of the present invention, when the photocurable resin layer further contains inorganic fine particles, the inorganic fine particles may be contained in an amount of about 1 to about 100 parts by weight, when the total weight of the cured resin is 100 parts by weight Or from about 10 to about 50 parts by weight. By including the above-mentioned inorganic fine particles in the above-mentioned range, it is possible to provide a light-cured resin layer excellent in both hardness and flexibility.

According to one embodiment of the present application, the photocurable resin layer may have a thickness of about 1 탆 or more, for example, about 1 to about 50 탆, or about 1 to about 20 탆. According to the present invention, by having the thickness as described above, it is possible to provide a light-cured resin layer having a thickness less than that of a film including a separate coating layer and a high hardness without causing curling or cracking.

The polarizing plate photo-curable resin layer of the present invention as described above is obtained by mixing the above-mentioned polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, a photopolymerization initiator, an antistatic agent and optionally an inorganic fine particle, The composition can be formed by photo-curing.

Examples of the organic solvent include alcohol solvents such as methanol, ethanol, isopropyl alcohol and butanol, alkoxy alcohol solvents such as 2-methoxyethanol, 2-ethoxyethanol and 1-methoxy-2-propanol, Ketone solvents such as ethyl ketone, methyl isobutyl ketone, methyl propyl ketone and cyclohexanone, propylene glycol monopropyl ether, propylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, Ether solvents such as diethylene glycol monomethyl ether, diethyl glycol monoethyl ether, diethyl glycol monopropyl ether, diethyl glycol monobutyl ether and diethylene glycol-2-ethylhexyl ether, benzene, toluene, The same aromatic solvent may be used alone or in combination.

The photocurable resin layer may include 0.1 to 2 parts by weight of the photopolymerization initiator and 1 to 10 parts by weight of the antistatic agent when the total weight of the cured resin is 100 parts by weight. In the above-mentioned numerical range, the photocurable resin layer may have desired sheet resistance, peeling electrification voltage, and peeling force.

On the other hand, the resin composition may contain the above-mentioned polyfunctional acrylate monomer, an acrylate oligomer having an elongation of 5 to 200%, an inorganic microfine particle, a photopolymerization initiator, an organic solvent, a UV absorber, a surfactant, , An antifouling agent, and the like, which are commonly used in the art to which the present invention belongs. The content thereof is not particularly limited as it can be variously adjusted within a range not lowering the physical properties of the photocurable resin layer of the present application.

According to one embodiment of the present application, for example, the resin composition may contain a surfactant as an additive, and the surfactant may be a 1 to 2 functional fluorine-based acrylate, a fluorine-based surfactant, or a silicone-based surfactant. At this time, the surfactant may be dispersed or crosslinked in the cured resin.

Further, the additive may include a yellowing inhibitor, and examples of the yellowing inhibitor include a benzophenone-based compound or a benzotriazole-based compound.

In addition, the release-treated surface may include any one selected from the group consisting of a silicone type and a melamine type. As a silicone type, a silicone resin generally used for mold release treatment can be used. The type of the melamine type is not particularly limited, but is selected from benzoguanamine-melamine-formaldehyde resin and melamine-formaldehyde resin It can be either.

The mold release treatment surface is provided on a surface of the protective film opposite to the photocurable resin layer to prevent adhesion between the protective film and the photocurable resin layer, thereby reducing friction caused by adhesion during peeling, thereby further lowering the peeling electrification voltage.

According to one embodiment of the present invention, the antistatic surface may include the antistatic agent. The description of the antistatic agent is the same as described above and therefore will be omitted.

According to one embodiment of the present application, the sheet resistance of the photocurable resin layer may be 10 ⁸ to 10 ¹² Ω / square or less.

According to an embodiment of the present application, the peeling electrification voltage of the photocurable resin layer may be 0.1 to 2 kV, and more specifically, 0.1 to 1 kV.

According to an embodiment of the present invention, the peeling force between the photocurable resin layer and the protective film may be 5 to 30 g / 2.5 cm, and may be 10 to 20 g / 2.5 cm.

The thickness of the photocurable resin layer of the present application is preferably 3 to 50 mu m. When the thickness is less than 3 μm, the sheet resistance is increased, and it is difficult to suppress the generation of static electricity when the protective film is peeled off. If the thickness is 50 μm or more, the mechanical properties such as crack resistance may be weakened.

According to an embodiment of the present application, a preservation layer containing a thermoplastic resin may be further included between the photocurable resin layer and the adhesive layer. The preservation layer may be provided to impart additional functionality to the polarizer.

Accordingly, the preserving layer may further comprise a photocurable resin containing a photocurable functional group. Heat resistance, moisture resistance, water resistance, thermal shock resistance and the like can be improved by the photo-curing resin containing the photo-curable functional group.

According to an embodiment of the present application, the thickness of the preservation layer may be 1 to 50 탆, and may be 1 to 20 탆.

In addition, the protective film is provided on one side of the photocurable resin layer, and a protective film commonly used in the art can be used.

The protective film is peeled off during the process of assembling the polarizing plate of the present invention, and it can be easily peeled while preventing the generation of static electricity in the process of peeling from the photocurable resin layer by the antistatic function of the photocurable resin layer. Further, when it is bonded, it can have a sufficient peeling force to serve as a protective film.

Referring to FIG. 2, one embodiment of the present application includes a backlight unit 200; A liquid crystal panel 300 provided on one surface of the backlight unit; And a polarizing plate 100 according to the present application provided between the backlight unit and the liquid crystal panel.

As used herein, the term " top surface " refers to a surface disposed facing the viewer when the polarizing plate is mounted on a device such as a liquid crystal display. And " upper " means a direction toward the viewer when the polarizing plate is mounted on the device. In contrast, 'bottom' or 'bottom' refers to a plane or direction that is oriented toward the opposite side of the viewer when the polarizer is mounted on the device.

The layer provided on the upper part or the lower part of the polarizing plate 100 is not limited to the structure shown in FIG. 2, but is a structure of a general liquid crystal display device. For example, a lower glass substrate, a thin film transistor, a liquid crystal layer, a color filter, an upper glass substrate, an upper polarizer and the like may be provided. Therefore, all of the layers shown in FIG. 2 may be modified or omitted, or other layers, substrates, films, sheets, and the like may be added as needed.

For example, the polarizing plate according to one embodiment of the present application may be applied to the upper polarizer, which is the outermost display of the display, not the portion in contact with the backlight unit.

Best Mode for Carrying Out the Invention Hereinafter, the function and effect of the present invention will be described in more detail through specific examples of the present invention. It is to be understood, however, that these embodiments are merely illustrative of the invention and are not intended to limit the scope of the invention.

Example 1

50 g of trimethylolpropane triacrylate (TMPTA), 20 g of DPCA120 (Nippon Kayaku, caprolactone denatured 6-functional group acrylate), 30 g of 9-EGDA (9-ethylene glycol diacrylate), 5 g of ionic compound FC4400 (3M) 1 g of product name Darocur TPO) and 100 g of Ethanol were mixed to prepare a coating solution. To give antistatic function, the coating solution was bar-coated on a PET film as a protective film having an antistatic surface. It was dried for 2 minutes at 60 ℃, by examining the D-bulb UV (200mJ / cm 2) in a nitrogen atmosphere to give the screen a resin layer having a thickness of sight 10㎛.

Example 2

50 g of pentaerythritol tri (tetra) acrylate, 50 g of 9-ethylene glycol diacrylate, 5 g of ionic compound FC4400 (3M), 1 g of photopolymerization initiator (trade name: Darocur TPO) and 100 g of ethanol were mixed to prepare a coating solution The coating solution was bar-coated on a 38 mu m PET film as a protective film having an antistatic surface. It was dried for 2 minutes at 60 ℃, by examining the D-bulb UV (200mJ / cm 2) in a nitrogen atmosphere to give the screen a resin layer having a thickness of sight 10㎛.

Example 3

50 g of trimethylolpropane triacrylate (TMPTA), 50 g of TA604AU (Japanese oil-retained ethylene oxide modified functional group acrylate), 5 g of ionic compound FC4400 (3M), 1 g of photopolymerization initiator (trade name: Darocur TPO) And the coating liquid was bar-coated on a 38 m PET film as a protective film having an antistatic surface to give an antistatic function. It was dried for 2 minutes at 60 ℃, by examining the D-bulb UV (200mJ / cm 2) in a nitrogen atmosphere to give the screen a resin layer having a thickness of sight 10㎛.

Example 4

In order to impart the antistatic function to the composition of Example 1, the coating liquid was bar-coated on a 38 m PET film as a protective film having an antistatic surface. This is dried at 60 ° C for 2 minutes and then irradiated with D-bulb UV (100 mJ / cm ² ) in a nitrogen atmosphere to produce a thickness of 5 μm. 20 g of PMMA (weight average molecular weight 150,000) and 80 g of MEK were bar coated and dried at 100 DEG C for 2 minutes to obtain a 10 mu m thick photocurable resin layer having a total thickness of 15 mu m. Then, a polarizing plate was produced together with a protective film having an antistatic surface on the back surface.

Example 5

A coating solution was prepared by mixing 100 g of C150 (product in which 20 nm SiO ₂ was dispersed in NMP TMPTA in Nano resin), 5 g of ionic compound FC4400 (3M), 1 g of photoinitiator (trade name Darocur TPO) The PET film, which is a protective film having a silicon release treatment surface, was bar-coated. It was dried for 2 minutes at 60 ℃, and the D-bulb UV 200mJ / cm ² irradiated in a nitrogen atmosphere to obtain a protective film having a thickness of 10㎛.

Example 6

The C150 (product in which the 20nm SiO ₂ dispersion 50% in TMPTA of Nano resin) 50g, EB9626 (SK entis Co., epoxy acrylate) 50g ionic compound FC4400 (3M) 5g, a photoinitiator (trade name Darocur TPO) 1g, Ethanol 100g To prepare a coating solution, and bar coating was applied to a PET film as a protective film having an antistatic surface / silicone release-treated surface. It was dried for 2 minutes at 60 ℃, and the D-bulb UV 200mJ / cm ² irradiated in a nitrogen atmosphere to obtain a protective film having a thickness of 10㎛.

Example 7

50 g of trimethylolpropane triacrylate, 50 g of 9-Ethylene glycol diacrylate, 5 g of ionic compound FC4400 (3M), 1 g of a photoinitiator (trade name: Darocur TPO) and 100 g of Ethanol were mixed to prepare a coating solution. Antistatic surface / The PET film, which is a protective film, was bar-coated. It was dried for 2 minutes at 60 ℃, and the D-bulb UV 200mJ / cm ² irradiated in a nitrogen atmosphere to obtain a protective film having a thickness of 10㎛.

Example 8

The coating solution of Example 1 was bar-coated on a PET film as a protective film having an antistatic surface / silicone release-treated surface and dried at 60 ° C for 2 minutes. Then, D-bulb UV was irradiated at 100 mj / cm ² To make a thickness of 5 탆. 20 g of PMMA (weight average molecular weight 150,000) and 80 g of MEK were coated by bar coating and dried at 100 DEG C for 2 minutes to obtain a protective film having a thickness of 10 mu m and a total thickness of 15 mu m.

Example 9

50 g of trimethylolpropane triacrylate (TMPTA), 20 g of DPCA120 (Nippon Kayaku, caprolactone denatured 6-functional group acrylate), 30 g of 9-EGDA (9-ethylene glycol diacrylate), 5 g of ionic compound FC4400 (3M) 1 g of product name Darocur TPO) and 100 g of Ethanol were mixed to prepare a coating solution. To give antistatic function, a PET film as a protective film having antistatic surface / silicone releasable surface was bar coated. It was dried for 2 minutes at 60 ℃, and the D-bulb UV 200mJ / cm ² irradiated in a nitrogen atmosphere to obtain a protective film having a thickness of 5㎛.

Example  10

50 g of trimethylolpropane triacrylate (TMPTA), 20 g of DPCA120 (Nippon Kayaku, caprolactone denatured 6-functional group acrylate), 30 g of 9-EGDA (9-ethylene glycol diacrylate), 5 g of ionic compound FC4400 (3M) 1 g of product name Darocur TPO) and 100 g of Ethanol were mixed to prepare a coating solution. To give antistatic function, a PET film as a protective film having antistatic surface / silicone releasable surface was bar coated. It was dried for 2 minutes at 60 ℃, D-bulb UV irradiated to 200mJ / cm ² to obtain a protective film having a thickness 3㎛ in a nitrogen atmosphere.

Comparative Example 1

50 g of pentaerythritol tri (tetra) acrylate, 9 g of 9-ethylene glycol diacrylate and 1 g of photopolymerization initiator (TPO) and 100 parts by weight of ethanol were mixed to prepare a resin composition. To give antistatic function, Bar was coated on a 38 [micro] m PET film as a protective film having a surface. This was dried at 60 ° C. for 2 minutes and irradiated with D-bulb UV (200 mJ / cm 2) to obtain a photocurable resin layer having a thickness of 10 μm.

Comparative Example 2

50 g of 9-EGDA (9-ethylene glycol diacrylate), 5 g of ionic liquid FC4400 (3M), 1 g of photopolymerization initiator (TPO) and 100 parts by weight of ethanol were mixed to prepare a resin composition, Bar coated on a 38 [mu] m PET film which is a protective film without a protective surface. This was dried at 60 ° C. for 2 minutes and then irradiated with D-bulb UV (200 mJ / cm 2) to obtain a photocurable resin layer having a thickness of 10 μm.

Comparative Example 3

50 g of 9-EGDA (9-ethylene glycol diacrylate), 1 g of photopolymerization initiator (TPO), and 100 parts by weight of Ethanol were mixed to prepare a resin composition, and a protective film 38 having no antistatic surface bar PET film. This was dried at 60 ° C. for 2 minutes and irradiated with D-bulb UV (200 mJ / cm 2) to obtain a photocurable resin layer having a thickness of 10 μm.

Comparative Example 4

A coating liquid was prepared by mixing 100 g of pentaerythritol tri (tetra) acrylate, 5 g of an ionic liquid FC4400 (3M), 1 g of a photopolymerization initiator (trade name: Darocur TPO) and 100 g of ethanol to prepare a coating liquid. . This was dried at 60 DEG C for 2 minutes, and then irradiated with D-bulb UV in a nitrogen atmosphere (200 mJ / cm2) to obtain a photocurable resin layer having a thickness of 10 mu m.

Comparative Example 5

(50% dispersion of 20 nm SiO2 in TMPTA of Nano resin), 50 g of EB9626 (SK entis, epoxy acrylate), 1 g of photoinitiator (TPO) and 100 parts of ethanol were mixed to prepare and prepare a resin composition, Bar coating was applied to a PET film as a protective film having a silicone release-treated surface free from the prevention function. After drying at 60 ° C for 2 minutes, D-bulb UV was irradiated at 200 mJ / cm ² to obtain a protective film having a thickness of 10 μm.

Comparative Example 6

50 g of EB9626 (SK entis, epoxy acrylate), 5 g of ionic compound FC4400 (3M), 1 g of a photoinitiator (trade name: Darocur TPO) and 100 g of Ethanol were mixed To prepare a coating solution, and bar coating was applied to a PET film as a protective film having a silicone release-treated surface free from antistatic function. This was dried at 60 DEG C for 2 minutes and then irradiated with D-bulb UV in a nitrogen atmosphere to obtain a protective film having a thickness of 10 mu m.

Comparative Example 7

A coating solution was prepared by mixing 50 g of C150 (50% dispersion of 20 nm SiO2 in NMP resin), 50 g of EB9626 (SK entis, epoxy acrylate), 1 g of photoinitiator (trade name Darocur TPO) / Protective film with silicone release treated surface PET film was bar coated. This was dried at 60 DEG C for 2 minutes and then irradiated with D-bulb UV in a nitrogen atmosphere to obtain a protective film having a thickness of 10 mu m.

Comparative Example 8

100 g of an ionic compound FC4400 (3M), 1 g of a photoinitiator (trade name: Darocur TPO) and 100 g of ethanol were mixed to prepare a coating solution, and an antistatic surface was prepared And bar-coated on a PET film not provided with a release-treated surface. This was dried at 60 DEG C for 2 minutes and then irradiated with D-bulb UV in a nitrogen atmosphere to obtain a protective film having a thickness of 10 mu m.

Comparative Example 9

50 g of trimethylolpropane triacrylate (TMPTA), 20 g of DPCA120 (Nippon Kayaku, caprolactone denatured 6-functional group acrylate), 30 g of 9-EGDA (9-ethylene glycol diacrylate), 5 g of ionic compound FC4400 (3M) 1 g of product name Darocur TPO) and 100 g of Ethanol were mixed to prepare a coating solution. To give antistatic function, a PET film as a protective film having antistatic surface / silicone releasable surface was bar coated. It was dried for 2 minutes at 60 ℃, and the D-bulb UV 200mJ / cm ² irradiated in a nitrogen atmosphere to obtain a protective film having a thickness of 1㎛.

Comparative Example 10

50 g of trimethylolpropane triacrylate (TMPTA), 20 g of DPCA120 (Nippon Kayaku, caprolactone denatured 6-functional group acrylate), 30 g of 9-EGDA (9-ethylene glycol diacrylate), 5 g of ionic compound FC4400 (3M) 1 g of product name Darocur TPO) and 100 g of Ethanol were mixed to prepare a coating solution. To give antistatic function, a PET film as a protective film having antistatic surface / silicone releasable surface was bar coated. It was dried for 2 minutes at 60 ℃, and the D-bulb UV 200mJ / cm ² irradiated in a nitrogen atmosphere to obtain a protective film having a thickness of 70㎛.

Production of Polarizer

Example 11

The photo-curable resin layer prepared in Example 1 was laminated and laminated with a 25 mu m PVA film so that the adhesive layer had a thickness of approximately 1 mu m using an acrylic adhesive, and the PET film was peeled off.

On the other side of the PVA, a polarizing plate was prepared by adhering an acrylic film having a thickness of 40 탆 in the same manner.

Example 12

The photocurable resin layer prepared in Example 2 was prepared in the same manner as in Example 9, except that the acrylic adhesive was used.

Example 13

The photocurable resin layer prepared in Example 3 was prepared in the same manner as in Example 9, except that an acrylic adhesive was used.

Example 14

The photocurable resin layer prepared in Example 4 was prepared in the same manner as in Example 9 except that an acrylic adhesive was used.

Example 15

The photocurable resin layer prepared in Example 5 was prepared in the same manner as in Example 9, except that an acrylic adhesive was used.

Example 16

The photocurable resin layer prepared in Example 6 was prepared in the same manner as in Example 9, except that an acrylic adhesive was used.

Example 17

The photocurable resin layer prepared in Example 7 was prepared in the same manner as in Example 9, except that an acrylic adhesive was used.

Example 18

The photocurable resin layer prepared in Example 8 was prepared in the same manner as in Example 9, except that an acrylic adhesive was used.

Example 19

The photocurable resin layer prepared in Example 9 was prepared in the same manner as in Example 9, except that an acrylic adhesive was used.

Example 20

The photocurable resin layer prepared in Example 10 was prepared in the same manner as in Example 9, except that an acrylic adhesive was used.

Comparative Example 11

The photo-curable resin layer prepared in Comparative Example 1 was laminated and adhered to the PVA film so that the thickness of the adhesive layer was approximately 1 占 퐉 using an acrylic adhesive, and the PET film was peeled off. On the other side of the PVA, a polarizing plate was prepared by adhering an acrylic film having a thickness of 40 탆 in the same manner.

Comparative Example 12

The photocurable resin layer prepared in Comparative Example 2 was prepared in the same manner as in Comparative Example 1 except that an acrylic adhesive was used.

Comparative Example 13

The photocurable resin layer prepared in Comparative Example 3 was prepared in the same manner as in Comparative Example 1 except that the acrylic adhesive was used.

Comparative Example 14

The photocurable resin layer prepared in Comparative Example 4 was prepared in the same manner as in Comparative Example 1, except that an acrylic adhesive was used.

Comparative Example 15

The photocurable resin layer prepared in Comparative Example 5 was prepared in the same manner as in Comparative Example 1, except that an acrylic adhesive was used.

Comparative Example 16

The photocurable resin layer prepared in Comparative Example 6 was prepared in the same manner as in Comparative Example 1 except that an acrylic adhesive was used.

Comparative Example 17

The photocured resin layer prepared in Comparative Example 7 was prepared in the same manner as in Comparative Example 1 except that an acrylic adhesive was used.

Comparative Example 18

The photocurable resin layer prepared in Comparative Example 8 was prepared in the same manner as in Comparative Example 1 except that an acrylic adhesive was used.

Comparative Example 19

The photocured resin layer prepared in Comparative Example 9 was prepared in the same manner as in Comparative Example 1 except that an acrylic adhesive was used.

Comparative Example 20

The photocurable resin layer prepared in Comparative Example 10 was prepared in the same manner as in Comparative Example 1 except that an acrylic adhesive was used.

How to measure

1) Thickness

And measured using a digital micrometer.

2) Pencil Hardness

Using a pencil hardness tester, the surface of the polarizing plate was reciprocated five times under a load of 500 g according to the measurement standard JIS K5400, and the hardness without scratches was confirmed.

3) scratch resistance

The steel wool # 0000 was subjected to a constant load, reciprocated 10 times, and a load without scratches was observed.

4) Sheet resistance

The measurement was performed under a condition of 100 V using a surface high resistance meter (Mitsubishi Chemical, Hiresta IP, MCP-HT260).

5) Peeling Voltage

(Sample shape: rectangle, sample size: aspect ratio (width: length) = 3: 4, diagonal length = 15 inches) at a temperature of 23 ° C and a relative humidity of 50%.

The constant voltage generated while peeling the film from each sample at a rate of 30 m / min was measured with a constant voltage meter (STATIRON-M2) at a height of 3 cm from the surface of the sample

6) Peel force

The polarizer prepared in the example was exposed to light of a polarizer and a photocurable resin layer at a condition of a peel rate of 0.3 m / min and a peel angle of 90 by using a physical property analyzer (Texture analyzer, Stable Microsystem, UK) Was measured.

7) High-speed peelability

(Protection) when the film is cleanly peeled off when it is peeled off, it is torn, or NG when the photo-cured resin layer is transferred to the protective film.

8) Crack resistance

A rod with a diameter of 10 mm was evaluated as good if no crack occurred when the photocurable resin layer was wound outward, and NG when the crack occurred.

Table 1 shows the case where only the antistatic surface is provided, and Table 2 shows the case where the surface with the release surface is provided.

Example 1 1 Example 12 Example 13 Example 14 Comparative Example 11 Comparative Example 12 Comparative Example 13 Comparative Example 14 Polarizer thickness
(After removing the substrate film) 76 μm 77 μm 76 μm 81 μm 76 μm 76 μm 76 μm 76 μm Pencil hardness 2H H H H H H H 3H My scratch 500g 300g 200g 300g 300g 300g 300g 700g Polarizer sheet resistance 10 ¹¹ 10 ¹⁰ 10 ¹⁰ 10 ¹⁰ over 10 ¹⁰ over 10 ¹² Protective Film Bottom Surface Resistance 10 ⁹ 10 ⁹ 10 ⁹ 10 ⁹ 10 ⁹ over Over 10 ⁹ Peeling Voltage (kV) 0.97 0.83 0.80 1.13 2.65 2.32 3.17 NG Peel force (g / 2.5 cm) 15.3 12.5 11.7 13.1 14.3 12.8 13.7 32.2 High-speed peelability Good Good Good Good Good Good Good NG

As shown in Table 1, the polarizing plate including the protective film having the photo-curable resin layer and the antistatic surface according to one embodiment of the present application has a desired performance in terms of pencil hardness and scratch resistance And has a suitable polarizer sheet resistance and a rear surface resistance value of the protective film, and has a relatively low peeling electrification voltage and peeling force, thereby reducing the damage caused by the static electricity which may occur when the protective film is removed.

Example 15 Example 16 Example 17 Example 18 Comparative Example 15 Comparative Example 16 Comparative Example 17 Comparative Example 18 Polarizer thickness
(After removing the substrate film) 76 μm 77 μm 76 μm 81 μm 76 μm 76 μm 76 μm 76 μm Pencil hardness 3H 2H H 3H 2H 2H 2H 3H My scratch 500g 400g 300g 500g 300g 300g 300g 700g Polarizer sheet resistance 10 ¹² 10 ¹¹ 10 ¹⁰ 10 ¹² over 10 ¹¹ over 10 ¹² Protective Film Bottom Surface Resistance 10 ⁹ 10 ⁹ 10 ⁹ 10 ⁹ Over over 10 ⁹ 10 ⁹ Peeling Voltage (kV) 0.75 0.45 0.36 0.92 2.80 1.83 2.26 NG Peel force (g / 2.5 cm) 12.9 13.5 31 36.4 14.2 13.3 13.7 32.2 High-speed peelability Good Good Good Good Good Good Good NG

As can be seen from Table 2, the polarizing plate including the protective film having the photocurable resin layer and the antistatic surface / release-treated surface according to one embodiment of the present application has a pencil hardness and scratch resistance It is possible to reduce the damage due to the static electricity which may occur when the protective film is removed because the peeling electrification voltage and the peeling force are relatively low while having suitable polarizer sheet resistance and backside sheet resistance value of the protective film.

Example 19 Example 20 Comparative Example 19 Comparative Example 20 Polarizer thickness
(After removing the substrate film) 71 μm 69 μm 67 μm 136 μm Pencil hardness H H F 3H My scratch 300g 200g 50g 500g Polarizer sheet resistance 10 ¹¹ 10 ¹² over 10 ¹⁰ Protective Film Bottom Surface Resistance 10 ⁹ 10 ⁹ 10 ⁹ 10 ⁹ Peeling Voltage (kV) 0.47 0.67 2.12 0.37 Peel force (g / 2.5 cm) 15.3 12.5 11.7 13.1 High-speed peelability Good Good Good Good Crack resistance Good Good Good NG

As can be seen from Table 3, when the thickness of the photocurable resin layer according to one embodiment of the present invention is 3 μm or less, the effect is inferior at the side of the polarizer sheet resistance. When the thickness of the photocurable resin layer is 50 μm or more It can be seen that the desired effect can not be obtained in the crack resistance.

100: polarizer
110: base film
120: adhesive layer
130: Photocurable resin layer
140: Protective film
200: Backlight unit
300: liquid crystal panel

Claims (20)

A base film;
An adhesive layer provided on one surface of the base film;
A photocurable resin layer provided on one surface of the adhesive layer; And
And a protective film provided on one surface of the photocurable resin layer,
The photocurable resin layer contains a polyfunctional acrylate monomer and a curing resin of an acrylate oligomer or acrylic elastic polymer having a elongation of 5 to 200%, a photopolymerization initiator and an antistatic agent,
Wherein the protective film has an antistatic surface on the other surface opposite to the surface facing the photocurable resin layer,
Further comprising a holding layer containing a thermoplastic resin between the photocurable resin layer and the adhesive layer,
Wherein the preserving layer further comprises a photocurable resin containing a photocurable functional group. The method according to claim 1,
Wherein the protective film further comprises a release-treated surface on a surface facing the photocurable resin layer. The method according to claim 1,
Wherein the curable resin has the polyfunctional acrylate monomer and an acrylate oligomer or an acrylic elastic polymer having a elongation of 5 to 200% at a weight ratio of 2: 8 to 8: 2. The method according to claim 1,
The polyfunctional acrylate monomer may be at least one selected from the group consisting of hexane diol diacrylate (HDDA), tripropylene glycol diacrylate (TPGDA), ethylene glycol diacrylate (EGDA), trimethylolpropane triacrylate (TMPTA), trimethylolpropane At least one member selected from the group consisting of trimethylolpropane triacrylate (TMPEOTA), glycerin propoxylated triacrylate (GPTA), pentaerythritol tetraacrylate (PETA), and dipentaerythritol hexaacrylate (DPHA) Containing polarizer. The method according to claim 1,
The acrylate oligomer has at least two acrylate functional groups and is at least one member selected from the group consisting of urethane, ethylene oxide, propylene oxide, and caprolactone. Lt; / RTI > The method according to claim 1,
Further comprising inorganic fine particles dispersed in the photocurable resin layer. The method of claim 6,
Wherein the photocurable resin layer comprises 1 to 100 parts by weight of the inorganic fine particles based on 100 parts by weight of the curable resin. The method of claim 6,
Wherein the inorganic fine particles comprise at least one selected from the group consisting of silica nanoparticles, aluminum oxide fine particles, titanium oxide fine particles and zinc oxide fine particles. The method of claim 2,
Wherein the release-treated surface comprises any one selected from the group consisting of silicon-based and melamine-based. The method according to claim 1,
Wherein the antistatic agent is any one selected from the group consisting of ionic compounds, conductive fine particles, and conductive polymers. The method according to claim 1,
Wherein the photocurable resin layer comprises 0.1 to 2 parts by weight of the photopolymerization initiator and 1 to 10 parts by weight of the antistatic agent based on 100 parts by weight of the curable resin. The method according to claim 1,
Wherein the antistatic surface comprises the antistatic agent. The method according to claim 1,
The sheet resistance of the photocurable resin layer is 1 X 10 ⁸ to 10 ¹² Ω / □. The method according to claim 1,
And a peeling electrification voltage of the photocurable resin layer is 0.1 to 2 kV. The method according to claim 1,
And a peeling force between the photocurable resin layer and the protective film is 5 to 30 g / 2.5 cm. delete delete The method according to claim 1,
The thickness of the photocurable resin layer is 3 to 50 占 퐉. The method according to claim 1,
Wherein the thickness of the preserving layer is 1 to 50 占 퐉. Backlight unit;
A liquid crystal panel provided on one surface of the backlight unit; And
And a polarizing plate according to claim 1 provided between the backlight unit and the liquid crystal panel.

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